In-package hydration, cooking, and pasteurization

ABSTRACT

This invention relates to a method for combining the multiple steps of hydration, cooking, and pasteurization of a food product into one simplified process. In one embodiment, this invention relates to a method for in-package hydration, cooking and pasteurization of a food product in a single step comprising (a) combining at least one low moisture food component and an aqueous based component in a heat-stable, sealable container wherein an effective amount of the aqueous based component is present to allow proper hydration and cooking; (b) sealing the heat-stable, sealable container; and (c) treating the sealed container at a temperature and time effective to hydrate, cook, and pasteurize the low moisture food product in a single step.

FIELD OF THE INVENTION

This invention generally relates to food processing. More specifically,this invention relates to a method for combining the multiple steps ofhydration, cooking, and pasteurization of a low moisture food product ina single process step. The food products which can be treated using themethods of this invention include, for example, dry pasta, dry rice,dehydrated potato, and the like, as well as mixtures thereof.

BACKGROUND OF THE INVENTION

“Ready to eat” and “ready to heat” food products are high in consumerdemand. The manufacture of these high quality processed foods typicallyinvolves multiple time consuming and labor intensive processes.Specifically, separate processes of hydration, cooking, andpasteurization are involved in the manufacture of these high qualityprocessed food products and are performed separately from each other. Asa result, such conventional processes require the use of multiplecontainers and process steps and utilize unnecessary energy. Moreover,excess solid and/or liquid wastes are produced from the execution ofthese processes in separate steps and containers.

The separate processes of hydration, cooking, and pasteurization are notnew in the art. In fact, in-package pasteurization is well known. Forexample, U.S. Pat. No. 6,797,308 (Sep. 28, 2004) relates to thestabilization of cooked pasta compositions against the development oftoxins and other contaminates. In essence, U.S. Pat. No. 6,797,308teaches a method of pasteurizing a food product inside its finalpackage.

U.S. Pat. No. 5,695,801 (Dec. 9, 1997) provides a method for producingshelf-stable, uncooked or partially cooked moist pasta by treating thepasta with steam, immersing the pasta in an aqueous solution containingacidulants and/or humectants, allowing the pasta to dry, sealing thepasta into a container, and pasteurizing the pasta within the containerusing conventional thermal processes.

U.S. Pat. No. 6,136,355 (Oct. 24, 2000) provides a process for themanufacture of instant cooking pasta or noodles by heating dry pastawith either wet or dry heat, drying the surfaces of the pasta if theheating is effected with wet heat, and packaging the pasta into asealable container. The food product is then later reheated within thepackage.

U.S. Patent Application, publication no. 20040156960, filed Feb. 10,2003, entitled “Food Product Preservation Method” teaches a method forpreservation of a food product which comprises combining a food productwith an amount of an edible acid to obtain an acidified food product,placing the acidified food product in a heat-stable, sealable container,sealing the container, pasteurizing the food product and then rapidlyreducing the temperature to below about 55° F. The food product is thenstored under refrigerated conditions and then later reheated.

Although previous methods have produced acceptable “ready to eat” and“ready to heat” food products, there remains a need for even furtherimprovements. These previous methods only teach in-packagepasteurization. They neither teach nor suggest in-package hydration,cooking and pasteurization in a single step. The present inventionaddresses these needed improvements. Indeed, the present method allowsthe various manufacturing processes of hydration, cooking, andpasteurization to be completed in a single step to obtain high qualityfinished products with consistent, and organoleptic pleasing, texturalproperties.

SUMMARY OF THE INVENTION

The present invention provides a method which allows the combination ofthe multiple steps of hydration, cooking, and pasteurization in a singlestep that occurs within a food product's sealed and final container. Thepresent invention reduces the number of containers and/or process steps,which can be translated into consumer friendly and lower cost products.In contrast to separate process steps using conventional processes, thepresent invention, by combining heating steps (e.g. cooking andpasteurization), also minimizes the total heat treatment received by thefinished food products, thus improve the organoleptic and nutritionalquality. Further advantages of the present method are the reduction ofliquid and solid waste, the utilization of less energy in themanufacture of these high quality processed food products, and reducedrisk of contamination since transfer of the food product from oneprocess to the next is eliminated.

More specifically, this invention relates to a method for in-packagehydration, cooking, and pasteurization of a low moisture food product ina single step, said method comprising (a) combining at least one lowmoisture food component and an aqueous based component in a heat-stable,sealable container wherein an effective amount of the aqueous basedcomponent is present to allow proper hydration and cooking; (b) sealingthe heat-stable, sealable container; and (c) treating the sealedcontainer at a temperature and time effective to hydrate, cook, andpasteurize the low moisture food product in a single step. The foodproduct within the sealed container preferably is agitated for at leasta portion of the time when it is treated at a temperature and timeeffective to hydrate, cook, and pasteurize the food product in a singlestep. The low moisture food components which can be used in the methodsof this invention include, but are not limited to, dry pastas, dry rice,dehydrated potatoes, dried cereals or grains, dried beans or legumes,dried vegetables, dried meats, dried seafood, dried spices or herbs, andthe like, as well as mixtures thereof. Generally, the preferred lowmoisture food components for use in the present invention are drypastas, dry rice, and dehydrated potatoes. The aqueous based componentswhich can be used in the methods of this invention include, for example,water, aqueous solutions, aqueous emulsions, aqueous dispersions,sauces, gravies, milk, whey, cream, syrups, juices, extracts, and thelike, as well as mixtures thereof.

In a preferred embodiment, this invention relates to a method forin-package hydration, cooking, and pasteurization of a low moisture foodproduct in a single step, said method comprising (a) combining at leastone low moisture food component and an aqueous based component in aheat-stable, sealable container wherein an effective amount of theaqueous based component is present to allow proper hydration andcooking; (b) adding at least one ingredient selected from the groupconsisting of preservatives, antioxidants, acidulants, stabilizers,salt, sweeteners, flavors, colorants, and combinations thereof; (c)sealing the heat-stable, sealable container; (d) treating the sealedcontainer at a temperature and time effective to hydrate, cook, andpasteurize the low moisture food product in a single step; (e) agitatingthe sealed container during at least a portion of step (d); and (e)cooling the hydrated, cooked, and pasteurized food product to a properstorage temperature. The at least one ingredient in step (b) may beadded or introduced into the container as a separate ingredient and/orwith the low moisture food component or aqueous based component in step(a).

DETAILED DESCRIPTION

This invention relates to a method for combining the multiple steps ofhydration, cooking, and pasteurization of a food product into asimplified, one-step process. This invention relates to a method forin-package hydration, cooking, and pasteurization of a low moisture foodproduct in a single step, said method comprising (a) combining at leastone low moisture food component and an aqueous based component in aheat-stable, sealable container wherein an effective amount of theaqueous based component is present to allow proper hydration andcooking; (b) sealing the heat-stable, sealable container; and (c)treating the sealed container at a temperature and time effective tohydrate, cook, and pasteurize the low moisture food product in a singlestep. The sealed container is preferably agitated during at least aportion of step (c). The low moisture food components which can betreated using the methods of this invention include, but are not limitedto, dry pastas, dry rice, dehydrated potatoes, dried cereals, driedgrains, dried beans, dried legumes, dried vegetables, dried meats, driedseafood, dried spices or herbs, and the like, as well as mixturesthereof. Generally, the preferred low moisture food components for usein the present invention are dry pastas, dry rice, and dehydratedpotatoes. The aqueous based components which can be used in the methodsof this invention include, for example, water, aqueous solutions,emulsions, or dispersions (e.g., acidulants, nisin-containingingredients, broths, and the like), sauces, gravies, milk, whey, cream,syrups, juices, extracts, and the like, as well as mixtures thereof.

The relative amounts of the low moisture food component and the aqueousbased component should be maintained at levels to provide an acceptablefinished food product. In one embodiment, the amount of aqueous basedcomponent should be sufficient to cover the low moisture food component.In another embodiment, the relative amounts should be adjusted so that,for the finished food product, most (e.g., greater than about 50percent), and in some cases essentially all of the water is absorbed. Inanother embodiment, the amount of the aqueous based component in theform of a sauce should be sufficient to maintain a sauce in the finishedfood product. In another embodiment, the relative amounts of lowmoisture food component and aqueous based component should be adjustedso that, the food component reaches optimum degree of hydration andtexture after the process. In yet another embodiment, the ratio of lowmoisture food component and aqueous based component is in the range ofabout 10:90 to about 70:30, and preferably about 20:80 to about 60:40.For a given low moisture food component, a given aqueous basedcomponent, and a given desired finished product, one of ordinary skillin the art can readily determine appropriate relative amount. Bycontrolling the amount of aqueous based component added to each sealedcontainer common textural defects due to under- or over-hydration thatcan occur with traditional hydration processes can be avoided.

The present invention represents a significant simplification in themanufacturing of high quality prepared foods (e.g., “ready to eat” or“ready to heat” foods). This simplified manufacturing process is madepossible by combining hydration, cooking, and pasteurization in a singleprocessing step and a single container. Secondary microbiologicalbarriers (e.g., acidulants, salt, chemical preservatives, biologicalpreservatives, and the like, as well as mixtures thereof) may also becombined with this simplified manufacturing process.

Preferably, the food products of this invention are contained in aheat-stable, sealable plastic pouch such that the food products can behydrated, cooked, and pasteurized directly in the pouch. Similarheat-stable, sealable containers that may be used in the method of thisinvention include cans, glass bottles, tubs, trays, and the like.Indeed, one of the advantages of the present invention is that themultiple processes of hydration, cooking, and pasteurization, whichwould conventionally occur in separate steps, can now occur in asimplified process in a single step thereby eliminating multipleprocesses and multiple containers.

In addition to the low moisture food component and the aqueous basedcomponent, additional ingredients may be added before the heat-stablecontainer is sealed. Such ingredients may include preservatives,acidulants, antimicrobials, bactericins, antioxidants, flavorants,colorants, spices, salt, seasonings, sweeteners, stabilizers, and thelike, as well as mixtures thereof. The addition of preservatives (e.g.,sorbic acid, benzoic acid, propionic acid, lactic acid, diacetic acid,and salts thereof as well as combinations thereof, acidulants (e.g.,food grade acids such as hydrochloric acid, sulfuric acid, metal acidsulfates, phosphoric acids, tartaric acid, fumaric acids, citric acid,lactic acid, gluconic acid, and the like), antimicrobials (e.g., nisin,nisin-containing cultured whey or milk, poly-L lysine, lysozyme,natamycin, and the like as well as combinations thereof), bactericins,and antioxidants will not only extend the shelf life of the finishedproducts, but it will also provide additional safety and/orpreservation. Such additives may be added as separate ingredients or maybe added with the aqueous based component (e.g., solution, slurry,emulsion, dispersion, or the like) and/or the low moisture foodcomponent. One especially preferred antimicrobial, nisin-containingwhey, which may be used in this invention is fully described in U.S.Pat. No. 6,110,509 (Aug. 9, 2000), U.S. Pat. No. 6,113,954 (Sep. 5,2000), U.S. Pat. No. 6,136,351 (Oct. 24, 2000), U.S. Pat. No. 6,242,017(Jun. 5, 2001), U.S. Pat. No. 6,613,364 (Sep. 2, 2003), and U.S. Pat.No. 6,797,308 (Sep. 28, 2004).

Prior to sealing the containing, the headspace above the food productand other ingredients may optionally be flushed with an inert gas (e.g.,nitrogen, carbon dioxide, steam, and the like) or may be reduced using apartial vacuum.

The sealed container containing the food product and other ingredientsis treated at a temperature and time effective to hydrate, cook, andpasteurize the food product in a single step. In other words, theheating profile should be effective in hydrating, cooking, andpasteurizing in a single step. Conventional heating equipment that maybe used includes, but is not limited to, water baths, submersioncookers, steamers, electrical ovens, gas ovens, infrared cookers,microwave cookers, and the like, as well as combinations thereof.Preferably, the sealed container is placed in a boiling water bath for atemperature and time effective to hydrate, cook, and pasteurize the foodproduct. Generally, the time necessary using a boiling water bath isabout 1 to about 60 minutes for a conventional sized pouch (i.e., oneholding about 20 to about 1000 g of food product) depending on thespecific low moisture food component used.

In the preferred embodiment, this invention also relates to a method forin-package hydration, cooking, and pasteurization of a food product in asingle step, said method comprising (a) combining at least one lowmoisture food component and an aqueous based component in a heat-stable,sealable container wherein an effective amount of the aqueous basedcomponent is present to allow proper hydration and cooking; (b) addingat least one ingredient selected from the group consisting ofpreservatives, antioxidants, acidulants, and any combinations thereof;(c) sealing the heat-stable, sealable container; (d) treating the sealedcontainer at a temperature and time effective to hydrate, cook, andpasteurize the low moisture food product in a single step; (e) agitatingthe sealed container for at least a portion of step d); and (f) coolingthe hydrated, cooked, and pasteurized food product to a proper storagetemperature.

The following examples are intended to illustrate the invention and noto limit it. Unless otherwise indicated, all percentages used in thepresent specification are by weight. All patents and publicationsreferred to in the present specification are hereby incorporated byreference.

EXAMPLE 1

In-package cooked/acidified shelf stable plain pasta. Dry shell pasta(about 60 g) was placed in a heat stable polyester pouch (about 5 byabout 6.5 inches; SealPAK from KAPAK Corp., Minneapolis, Minn.). Asodium acid sulfate aqueous solution (0.7%; about 86 g) was added to thepasta in the pouch. Most of the air was evacuated from the pouch and thepouch was sealed. The pouch was mixed slightly and then placed in aboiling water bath. The pouch was agitated frequently in the water bathuntil the liquid was absorbed by the pasta (about 20 minutes). The pouchwas removed from the boiling water and immediately cooled in cold wateruntil the product reached room temperature. This process yielded fullycooked acidified shelf stable pasta at a pH of about 3.8; the producthad excellent properties and was microbiologically stable for at leastsix months under ambient conditions.

EXAMPLE 2

In-package cooked/acidified shelf stable macaroni and cheese. Anacidified sauce mixture of 45% of 0.7% aqueous sodium acid sulfate, and55% of acidified cheese flavor sauce was prepared. The acidified cheeseflavor sauce consisted of about 1.5% cheese powder, about 4.5% starchand gums, about 11% bulking agents (i.e., corn syrup solid andmaltodextrin), about 9% butterfat, about 1.6% salt, about 0.18% TiO₂,about 0.45% emulsifiers, about 0.15% colors, about 0.3% flavors. The pHof the sauce mixture was about 3.85. Dry shell pasta (about 46 g) andacidified sauce mixture (150 g) was placed in a heat stable plasticpouch, as used in Example 1. Most of the air in the package wasevacuated and the pouch was sealed. The pouch was mixed slightly andthen placed in a boiling water bath. The pouch was agitated frequentlyin the water bath in the first phase of the cooking process. The pouchcontaining the pasta was removed from the boiling water bath after about22 minutes and immediately cooled in cold water until the productreached temperature. This process yielded fully cooked, acidified, andpasteurized shelf stable macaroni and cheese at a pH of about 3.8; theproduct was microbiologically stable for at least six months underambient conditions.

EXAMPLE 3

Refrigeration stable in-package cooked plain pasta. A nisin-containingcultured sugar solution was prepared to contain about 500 lU/ml of nisinequivalent activity (e.g., 1.0% Danisco Guardian CS1-50 in water). Driedshelf stable pasta (about 56 g) and the nisin-containing solution (about81 g) were placed in a heat-stable, sealable plastic pouch. Most of theair in the pouch was evacuated and the pouch was sealed. The pouch wasmixed slightly and then placed in the boiling water bath. The pouch wasagitated frequently in the water bath. The pouch containing the pastawas removed from the boiling water bath after about 20 minutes, when allthe liquid was absorbed by the pasta. The heat treated pouch was cooledin cold water until it reached a refrigerated temperature of about 40°F. This process yielded fully cooked refrigeration stable pasta thatcontains about 450 lU/g of nisin equivalent activity and has a pH ofabout 5.2; the product had excellent sensory properties and nisinactivity was maintained for at least six weeks under refrigerationstorage.

EXAMPLE 4

Refrigeration stable in-package cooked pasta and sauce. Nisin-containingcultured milk was added to dairy based cheese sauce to yield a nisinequivalent activity of about 400 lU/g (e.g., 0.8% Danisco GuardianCS1-50). Dried shelf stable pasta (48 g) was placed in a heat-stable,sealable plastic pouch. The nisin-containing dairy based cheese saucewas added to the pouch and most of the air was evacuated from the pouch.Evacuating the air inside the pouch could be achieved with, among othermethods, a vacuum or with nitrogen flushing. The pouch was then placedin a boiling water bath and agitated for approximately 22 minutes oruntil the pasta was fully cooked. The pouch was then removed from thewater bath and cooled quickly in a cold water bath. The process yieldedfully cooked pasta in sauce that contained about 300 lU/g of nisinequivalent activity and had a pH of about 5.22. This pasta in sauceproduct, which had excellent organoleptic properties, was stable underrefrigerated conditions for at least about three months; nisin activitywas essentially unchanged after this storage period.

Other pasta and sauce (e.g., Alfredo) combinations can be prepared andused in a similar manner.

1. A method for in-package hydration, cooking, and pasteurization of afood product in a single step, said method comprising: (a) combining atleast one low moisture food component and an aqueous based component ina heat-stable, sealable container wherein an effective amount of theaqueous based component is present to allow proper hydration andcooking; (b) sealing the heat-stable, sealable container; and (c)treating the sealed container at a temperature and time effective tohydrate, cook, and pasteurize the low moisture food product in a singlestep.
 2. The method as defined in claim 1, wherein the sealed containeris agitated during at least a portion of step (c).
 3. The method asdefined in claim 1, wherein the low moisture food component is selectedfrom the group consisting of dry pastas, dry rice, dehydrated potatoes,dried cereals, dried grains, dried beans, dried legumes, driedvegetables, and mixtures thereof.
 4. The method as defined in claim 1,wherein the aqueous based component is selected from the groupconsisting of water, aqueous solutions, aqueous emulsions, aqueousdispersions, sauces, gravies, milk, whey, cream, syrups, juices,extracts, and mixtures thereof.
 5. The method as defined in claim 1,wherein the effective amount of the aqueous based component is an amountsufficient to cover at least the low moisture food component.
 6. Themethod as defined in claim 1, wherein the ratio of the low moisture foodcomponent and the aqueous based component is in the range of about 10:90to about 70:30.
 7. The method as defined in claim 1, wherein at leastone of the ingredients selected from the group consisting ofpreservatives, acidulants, antimicrobials, bactericins, antioxidants,flavorants, colorants, spices, salt, seasonings, sweeteners,stabilizers, and mixtures thereof is added to the container prior tosealing.
 8. The method as defined in claim 3, wherein an acidulant isadded to the container prior to sealing.
 9. The method as defined inclaim 3, wherein an antimicrobial agent is added to the container priorto sealing and the antimicrobial agent is selected from the groupconsisting of nisin, nisin-containing cultured whey or milk, poly-Llysine, lysozyme, natamycin, and combinations thereof.
 10. The method asdefined in claim 3, wherein a preservative is added to the containerprior to sealing and the preservative is selected from the groupconsisting of sorbic acid, benzoic acid, propionic acid, lactic acid,diacetic acid, and salts thereof as well as combinations thereof. 11.The method as defined in claim 1, wherein an antioxidant is added to thecontainer prior to sealing.
 12. The method as defined in claim 3,wherein an antioxidant is added to the container prior to sealing. 13.The method as defined in claim 4, wherein an antioxidant is added to thecontainer prior to sealing.
 14. The method as defined in claim 1,wherein the heat-stable, sealable container is a plastic pouch.
 15. Themethod as defined in claim 3, wherein the heat-stable, sealablecontainer is a plastic pouch.
 16. The method as defined in claim 4,wherein the heat-stable, sealable container is a plastic pouch.
 17. Amethod for in-package hydration, cooking, and pasteurization of a foodproduct in a single step, comprising: (a) combining at least one lowmoisture food component and an aqueous based component in a heat-stable,sealable container wherein an effective amount of the aqueous basedcomponent is present to allow proper hydration and cooking; (b) addingat least one of the ingredients selected from the group consisting ofacidulants, antimicrobials, antioxidants, flavorants, and mixturesthereof; (c) sealing the heat-stable, sealable container; (d) treatingthe sealed container at a temperature and time effective to hydrate,cook, and pasteurize the low moisture food product in a single step; (e)agitating the sealed container simultaneously with at least a portion ofstep (d); and (f) cooling the hydrated, cooked, and pasteurized foodproduct to a proper storage temperature.
 18. The method as defined inclaim 17, wherein the low moisture food component is selected from thegroup consisting of dry pastas, dry rice, dehydrated potatoes, driedcereals, dried grains, dried beans, dried legumes, dried vegetables, andmixtures thereof.
 19. The method as defined in claim 18, wherein theaqueous based food component is selected from the group consistingwater, aqueous solutions, aqueous emulsions, aqueous dispersions,sauces, gravies, milk, whey, cream, syrups, juices, extracts, andmixtures thereof.
 20. The method as defined in claim 18, wherein theeffective amount of the aqueous based component is an amount sufficientto cover at least the low moisture food component.
 21. The method asdefined in claim 18, wherein the ratio of the low moisture foodcomponent and the aqueous based component is in the range of about 20:80to about 60:40.
 22. The method as defined in claim 18, wherein theheat-stable, sealable container is a plastic pouch.